Many systems currently employ light absorbing devices in photodetection and imaging. Conventional light absorbing devices generally include structures, such as quantum dots, gratings, and clusters, which are configured to excite (e.g., absorb) electrons in response to a particular wavelength of incident electromagnetic radiation (hereinafter “radiation”). Conventional light absorbing devices generally only absorb a narrow bandwidth of radiation. In general, the structures may resonantly enhance the local surface electromagnetic field (i.e., |E(w)2|) from the dipolar enhancement effect for incident radiation. The structures of conventional light absorbing devices generally have three dimensions (x, y, z) that may all be varied in order to tune the structure to a desired excitation wavelength. The excitation wavelength may increase as the dimensions of the structures increase. Each dimension of the structures may have its own associated excitation wavelength. As a result, when more than one dimension is varied, there may be an interaction among excitation wavelengths from the different dimensions, which may cause interference for determining the overall excitation wavelength of the material. The interference may result in relatively large dimensions being needed for the three dimensions of the device structures in order to obtain a relatively long excitation wavelength. The relatively large dimensions may cause interference in the excitations in the multiple dimensions, which interference may limit the range of excitation wavelengths, as well as reduce the strength of the excitations.
The inventors have appreciated that there is a need for improved light absorbing devices, including photonic nanostructures, which may decrease interference in the excitations, improve the range of the excitation wavelengths, increase the strength of the excitations, and improve efficiencies of devices that may employ such light absorbing devices, among other benefits.